How to Flush Your Hot Water Heater in Six Easy Steps

Do you remember the last time you flushed your water heater? Has it recently started making loud popping sounds, especially after you’ve had a hot shower?

If it’s been more than a year or two, and your hot water no longer seems to meet your demand, it’s probably time to flush your water heater tank. Luckily, draining your water heater is a relatively simple job you can complete with tools you probably already have.

Your water supply type is the biggest factor when determining how often you’ll need to drain your water heater. Depending on where you live, most homeowners need to flush their water heaters every 1-3 years. Houses in areas with mineral-filled hard water require more water heater maintenance than houses in soft water areas.

Why do I need to drain my water heater?

As you use your hot water, sediment builds up in the tank from the water supply. Over time, the sediment settles at the bottom of the tank, which creates a layer between the heating element and the water. If you hear popping or crackling noises coming from your water heater, it’s usually from air bubbles traveling through the sediment.

When left to accumulate, this sediment will drastically decrease the life of your water heater and steadily increase your energy bill. With a layer of sediment to work though, the water heater has to work harder to get the water up to temperature.

Other signs that indicate that it’s time to drain your water heater include seeing visible sediment in your hot water and hot water that runs out quickly.

Gather your supplies

Before you get started, you need to gather the tools and supplies you need to drain your water heater. For this project, you will need:

Channel locks

Screwdriver

Garden hose

Towels

Gloves

1. Turn off the water heater.

For your safety, make sure you turn the power to the water heater completely off. Water and electricity don’t mix. DO NOT proceed if you’re not sure you’ve properly shut off the power.

If your water heater has a sticker with shutdown instructions, follow those. If not, here are the basics:

Gas. Turn the thermostat on the water heater to the “pilot” setting. To be extra cautious (and/or if recommended for your unit) you can turn it to “off” and also shut off the gas supply to the unit. If you have a physical pilot light, this means you’ll have to relight it later.

Electric. Locate the breaker for the water heater and flip it to the “off” position.

Safety note: Even with the heating elements turned off, the water in the tank may remain scalding hot for hours. The pipes and even the unit itself may be very hot. To be careful, wait several hours or overnight for the water to cool. When working around a hot water heater, take care to avoid contact with any water and make sure to drain hot water away from where it can cause harm. Protective gloves are recommended. Err on the side of caution and assume the water is hot!

2. Turn off the cold water to the water heater.

Most water supplies are located on the top of the water heater. Turn the water supply to the “off” position.

3. Attach a drain hose.

Near the bottom of the tank, locate the drain valve and attach a garden hose. Any standard garden hose will work. Run the hose so that water can easily flow out of the tank into a drain or outside of your house.

4. Open a hot water tap in your house.

In a nearby sink, turn on the hot water tap. This will help the water heater drain quickly. If that sink has an aerator attached to the nozzle, remove it. Sediment from the water heater could clog the tap as the water heater’s supply gets lower.

5. Open the drain valve.

With the hose securely attached, loosen the drain valve. For some water heaters, you need a screwdriver to loosen the valve. Other water heaters have a handle you can turn with your hand or channel locks. Be careful, the water coming out of the heater may still be hot. After the water has finished draining from the tank, use the cold water supply to the heater to flush out the remaining sediment.

6. Clean up.

Once the water from the drain valve is running clear, do the following:

Close the drain valve.

Remove the drain hose.

Turn off the hot water tap and reattach the aerator, if equipped.

Turn on the cold water supply to the water heater. Fill the heater with water to avoid damaging the heating elements when power is restored.

Turn on the electricity or gas to the heater.

Clean up any water that leaked during the process.

If you have trouble getting your water heater to drain, or if you’re still having problems with your hot water, call the experts at Raby Plumbing at 918-200-9906. For more water heater tips, check out our article on How To Maintain a Water Heater.

Resources found on our website are provided as general guidelines, and Raby Plumbing does not assume any liability resulting from the provided information.